Weeding the Web

Tree following: lilac growing apace

I missed reporting on the lilac last month because there really didn't seem to be much different from April and the run-up to Chelsea Flower Show kept my eye off this particular ball. (Incidentally, if you do look, you might notice that we now have a lovely new colour for the garage door.)

The flowers are now past and I've cut off the seed heads (this is very easy at the moment, given its height). What has been noticeable is the energy it's put into powering upwards.

Where the flowers were around head height, now the tips of the branches are at least a foot higher. It's bushing out without my help.

There are a couple of leaves with the brown patches I noted last year...

...and the sawn-off trunk is taking on an age and patina that's very attractive.

I'm still wondering whether I should cut back some of the branches to encourage branching lower down, but on balance I think I'll leave it. They've naturally started branching at about head height - what makes them start there, I wonder, and not lower down?

 

As you can see, they're thickening up nicely and I get the impression that the lilac needs none of my help at all.

This is part of Lucy Corrander's monthly Tree Following meme. See more at Loose and Leafy.

Tree following: new year, same lilac

I'm a bit tardy rejoining the Tree Following meme with Lucy at Loose and Leafy but there really wasn't anything to report last month. Suddenly, in the last few weeks the buds have sprung into action and - yes! - we have flowers. 

The tallest branch is now above my head, having spent all winter on a par with it. What should I do? Cut it back to one branch to try to create a new tree, or give it its head as a shrub.

For now, I'm settled on a shrub. It would be a shame to miss all those flowers.

If you were following last year, you'll know that I tried to root a cutting. It was looking pretty good, and until recently the tiny leaf buds were green.

But now they're brown. This is not, I fear, a good sign...

(If you're wondering what happened to this lilac last year, here's where it all started.)

Tree Following: relaxing into winter

There's a certain resemblance to a bog-brush (or five) about the lilac at the moment. The shoots have lost some of their middle leaves, so there's bunch at the bottom and a few at the top.

The rest are continuing to brown.

A spider has found one a useful anchoring point:

And there's a pleasing hint of life awaiting the spring:

How will it fare next year, I wonder?

To follow more trees around the world this month, visit Loose and Leafy.

Apple scab takes over

How are your apples? Mine look absolutely ghastly. Our unnamed 25 year-old variety that ripens round now is, pretty much, one big scab.  OK, so the fruit is still broadly edible, but some of the scab is so bad that it's cracked, and those apples will have to be used asap before disease creeps in.

All parts of a tree can be affected, and scab also causes early leaf fall and thus weakens the tree if it continues for several seasons.

Not every apple gets scab. Our Egremont Russet has escaped, faithfully living up to its reputation as one of the numerous varieties that are extremely scab resistant. So what happened to the anonymous variety this year? There's often a bit of scab, but on nothing like the scale we're seeing now.

What is Apple Scab?

Apple scab is a fungus (Venturia inaequalis) which overwinters on fallen leaves. You have to admire Nature. Maturity of spores, rather magically, coincides with the development of the tree, and their release begins with bud-break, when the leaves first emerge (a time also known as "green-tip"). By the time the blossom is over, most spores have matured, spurred on by periods of weather most conducive to tree growth (when, presumably, they're somehow alerted to the presence of fresh "flesh").

The number of spores released is, as you can imagine, directly related to the number of infected leaves left over from the previous season. A 1-3% increase in infected leaves on the ground is likely to result, the following spring, in a 10% increase of spores released at green-tip; a 5% increase leads to a ten-fold increase in spores. (Source: Apple Scab Disease Management video from MSU).

Mature spores are released in wet weather, about half an hour after rain begins (fascinatingly, if it rains at night, spores don't usually spurt forth until daybreak - fungus afraid of the dark?). They're blown by wind onto fruit and leaves, which need to be wet for them to germinate. They will then infect the apple if conditions are favourable. For example, if leaves and fruit stay wet for 23 hours at an average 5.5 degrees Centigrade (42F), or 9 hours at 16-24 degrees C (61-75F), then lesions will appear in approx 3 or 2 weeks respectively. 

Spores from these new lesions are dispersed by rain throughout the season and - wouldn't you know it? -  these these lesions release even more spores than are coming from the lesions on leaves on the ground.  So infection continues, although leaves are completely resistant once they're full grown, and only succumb again once their cuticles begin to crack. Fruit also becomes more resistant, though late scab infection can develop in stored fruit.

Why this year?

April and May were warmer than average for most in the UK, and in April and May we had plenty of rain in the south, so it's not surprising that fungus flourished.

But not without a little help, you're no doubt thinking.

And you'd be right - I never clear up leaves. Combine this with the weather and the result are obvious to all. But enough of my sluttish ways. This year every single leaf is coming out from under that tree.  Yes, there are sprays that can be employed at strategic moments in spring, but let's see if a little garden hygiene won't go a long way. 

Annoyingly, as the tree tends to bear biennially, if it does work I won't enjoy the fruits of my labour until 2016.

(Incidentally, if you'd like more science, Cornell University has a useful Apple Scab factsheet. And so does the Horticultural Development Company.)

 

 

 

Tree Following: autumn's progress

This month shows mostly signs of autumn on the lilac. At least, I hope they are, rather than something gradually eating away at the tree. The leaves are browning, but they are also getting eaten.

Not something that happened when it was a tree, but then perhaps the snails that like to call the lilac home didn't climb so willingly.  At least they're pretty ones.

I guess it was to be expected that the shoots (can I call them branches now?) would stopped growing. The lilac is no taller than it was last month.

Time to take a closer look at the sawn-off end of the stump.

 

And here's what it looked like back in May. The markings are darker now but I don't think they've spread.

 
And finally, Baby Lilac:

The tiny new leaf has gone brown and fallen, and there's just this left now. I suspect there'll just a stump to see next month. I must remember to not to let it dry out over winter.

To see how other trees are faring around the world, hop over to Loose and Leafy.

Tree Following: does the lilac know it's autumn?

Well, despite the anxieties of last month, the lilac is continuing to grow and its tallest shoot is now  taller than I am.

The leaves that last month were looking brown round the edges and wilted are now, additionally, somewhat frayed. Have they been eaten because they weren't doing so well or is it all part of the original problem?  I'm not sure what's had them, as there's been no sign of pests when I've been around.

However, whatever it is hasn't spread enough to do any obvious weakening. Some of the other leaves are beginning to brown, but this I recognise. The lilac always seems to turn autumnal before the other trees in the vicinity, and every year I see leaves like that below and wonder what's wrong with them, until I remember that they have to drop some time.

Meanwhile, what on earth is going to happen to the cutting?  The new leaf, as you can see has hardly grown since last time. I fear it has ground to a halt, but why? Because it actually isn't going to root, or because this cutting too is getting the message about autumn? One leaf has already dropped off (though it didn't turn brown). I'm keeping it damp and no longer keep it under a plastic bag as the soil was beginning to go mouldy. Fingers crossed.

This is part of Lucy's Tree Following meme at Loose and Leafy. Why not pop over and see what's happening to trees around the world?

Tree following: a new baby lilac?

A month on, and my downed lilac is turning into quite a bush.

If you dropped by last month, you'll know that some of the young shoots had turned black at the end and one of the shoots had wilted. I'm grateful for the helpful observation from Tim Havenith of Notes of Nature.

On the stem that has died back, did you notice if it had wilted first? If so, it might indicate a fungal infection blocking the vascular elements. In which case you should cut the wilted stems off and either burn them or put them in the green bin if you have one. Fingers crossed it'll be ok.

Well, the stems didn't seem to have wilted before turning black, so I breathed a sigh of relief at that, but kept a close eye in case of developments.

New shoots have been growing fresh and strong.

Some of the leaves on the older shoots appear to be suffering some sort of virus attack, but it's not widespread.

The browning edges are causing me some concern, though. Again, these are on the tallest shoot. On the other hand, I know I've been taken by surprise by this lilac before, when I've wondered why leaves are looking manky and realised that it's merely the onset of autumn. Bit early, I know, but everything seems to be several weeks advanced this year.  On the other hand, these do look rather wilted too. Perhaps Tim's right about a vascular problem?

Finally, what of the babies - the cuttings I took last month?  Well, the smaller one sat there and did nothing and began to look sorry for itself. That's gone, I'm afraid. But the other shows distinct signs of possible success, with a new leaf beginning to unfurl.

This is part of Lucy's Tree Following meme at Loose and Leafy. Why not pop over and see what's happening to trees around the world?

Tree Following: lilac puzzle time

Well, the lilac is bushing out, and the leading shoot is around three feet long now. I might even have to take the shoot nearest the wall away, as it looks set to jut over the pavement.

There are some odd things going on, though. Some of the youngest shoots have gone black and died off.

One of the larger shoots seems to be wilting.

And the lower leaves on the strongest shoots have grown enormous. The picture shows one covering my hand.

Does the tree do this to try to gain more photosynthesis?  My fear is that the root system is too great to be sustained by the current leaf area and the tree is trying to compensate (if you have an opinion on this, please feel free to chip in. I'm merely supposing here). That might explain the dead shoots, too.

So, will Husband turn out to be right - the tree will run out of energy, albeit more quickly than he supposed?  Anyway, it's engendered another experiment. Bob Flowerdew recently opined on Gardeners' Question Time that it was extremely difficult to get lilac cuttings to take. But most people aren't taking brand-new growth straight from the trunk, so I thought I'd have a go. I've got a couple going - one of the very short, new crinkly leaved shoots, and one of the slightly older, soft growth. Both I tore off at the base.

They spend most of their time under a plastic bag with holes cut in it, but I removed that for posing purposes. We'll just have to see what happens. The soft growth wilted but has now perked up, so I'm mildly hopeful that something may come of it.

This is part of Lucy's Tree Following meme at Loose and Leafy, where she's discovered that her pine "talks". Why not pop over and see what's happening around the world?

Tree Following: lilac tree still bursting at the seams

I don't think we can expect a particularly startling advance on last month's sprouts. They're bigger, and the one at the top on the sunniest side is the longest. However, all are continuing to grow and, unexpectedly (for me, anyway), new buds are still breaking through. What, I wonder will be the best way to deal with them all? I think a judicious bit of pruning will be called for eventually.

   

This is part of Lucy Corrander's Tree Following meme at Loose and Leafy. Visit to see how other trees are progressing around the world.

Tree Following: lilac recovery?

Garden bloggers around the world have been galvanised into action by Lucy Corrander of Loose and Leafy with her Tree Following meme. At the last count, seventy-six people across seven countries now keep a monthly eye on a tree of their choice and report back. It's addictive stuff. You can keep up with a tamarillo in Melbourne, a Kousa Dogwood in Michigan or a Mulberry in Suffolk. Or, indeed, a rather sorry lilac in southern England. Mine.

Back in October, I reported on the lamented demise of our much-loved lilac in the front garden. St Jude, the patron saint of lost causes, had sent a storm to create a few of his own.  At least, a lost cause is what I assumed it to be.

Just as I'd decided to follow my Bramley apple (showing a lot of blind wood, it offers the chance to check up on the effects of my pruning) I spotted the lilac. Despite being sawn in half, like a magician's assistant, leaving a bare stump which we intended to revisit with the chainsaw, in the last three weeks or so buds have burst from the stump.

The stump is still leaning at an angle of 45 degrees, so we're storing up problems if it grows too big. But I can't bear to dig it up now. New life is surging and it looks as if perhaps we'll have ourselves a bush, rather than a tree.

Or perhaps, as Husband suggests, it'll run out of steam in a couple of years and give up the ghost. We'll just have to wait and see. In the meantime, the snails seem particularly fond of it.